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In Japan, the production of traditional handmade Japanese paper using the spring water has been performed in the Shuso area of Shikoku Island. However, the method of production was been handed down by trial and error and observation of the expert movement until now. The produced papers are counted one unit that is five hundred sheets of Japanese paper. Five hundred sheets of Japanese paper are called 1 [lot]. The paper has two type of thickness and its size is 600mm × 1500mm. Thick paper is 9[kgf] per lot. The other hand, thin paper is 8[kgf] per lot. In other words, the expert is making paper which is the difference of 2[gf] per sheet. This time, we have been able to obtain cooperation with traditional craftsman for the digitizing of his skills. Therefore, we visualize the tacit knowledge of the expert’s skill. The expert subject has 34 years of experience of traditional hand-made Japanese paper. We have digitized his manufacturing movement by using motion capture. His movements are analyzed by attaching infrared reflective markers of 20 on each parts of the body. In this study, we found that constant rhythm of the neck in handmade Japanese paper manufacturing movement. Furthermore, the first scoop is performed at the time much shorter than in the case of other scoops.

Myosin IXb, a member of the myosin superfamily, is a molecular motor that possesses a GTPase activating protein (GAP) for Rho. Through the yeast two-hybrid screening using the tail domain of myosin IXb as bait we found BIG1, a guanine nucleotide exchange factor for ADP-ribosylation factor (Arf1), as a potential binding partner for myosin IXb. The interaction between myosin IXb and BIG1 was demonstrated by co-immunoprecipitation of endogenous myosin IXb and BIG1 with anti-BIG1 antibodies in normal rat kidney cells. Using the isolated proteins, it was demonstrated that myosin IXb and BIG1 directly bind to each other. Various truncation mutants of the myosin IXb tail domain were produced, and it was revealed that the binding region of myosin IXb to BIG1 is the zinc finger/GAP domain. Interestingly, the GAP activity of myosin IXb was significantly inhibited by the addition of BIG1 with IC(50) of 0.06 microm. The RhoA binding to myosin IXb was inhibited by the addition of BIG1 with the concentration similar to the inhibition of the GAP activity. Likewise, RhoA inhibited the BIG1 binding of myosin IXb. These results suggest that BIG1 and RhoA compete with each other for the binding to myosin IXb, thus resulting in the inhibition of the GAP activity by BIG1. The present study identified BIG1, the Arf guanine nucleotide exchange factor, as a new binding partner for myosin IXb, which inhibited the GAP activity of myosin IXb. The findings raise a concept that the myosin transports the signaling molecule as a cargo that functions as a regulator for the myosin molecule.